Cardiovascular risk factors in mild cognitive impairment and dementia

Abstract

Abstract Background and Aim: The subcortical small vessel type of dementia (SSVD) is a common but poorly characterized type of vascular cognitive impairment. This thesis aimed to investigate biomarkers and cardiometabolic risk factors in SSVD during its progression from subjective cognitive impairment (SCI) or mild cognitive impairment (MCI) to dementia. Methods: Patients with SSVD, Alzheimer’s disease (AD), mixed dementia (combined SSVD and AD), and healthy controls were enrolled from the longitudinal Gothenburg MCI study. The aim was to investigate if SSVD can be identified by cerebrospinal fluid (CSF) biomarkers (Study I), if SSVD is associated with a specific cardiometabolic profile (Study II), and if lipid variables (Study III) or Homeostatic Model Assessment of Insulin Resistance (HOMA-IR; Study IV) are associated with the risk of incident SSVD. Results: In Study I, the combined use of CSF neurofilament light chain and CSF soluble amyloid precursor protein-β had a high ability to separate SSVD patients from healthy controls. In Study II, SSVD patients had a higher prevalence of hypertension and diabetes compared with AD patients, patients with mixed dementia, and healthy controls. Furthermore, low baseline serum high-density lipoprotein-cholesterol (HDL-C) and elevated baseline triglyceride/HDL-C ratio (Study III) and impaired baseline HOMA-IR (Study IV) were associated with increased risk of conversion from SCI or MCI to clinically manifest SSVD. Conclusion: The results suggest that SSVD is characterized by a specific profile of CSF biomarkers and cardiometabolic variables. Furthermore, low serum HDL-C and impaired HOMA-IR were associated with increased risk of progression to manifest SSVD, which may provide opportunities for early disease prevention.